i can help with that :
First go to your google console cloud and there go to api and services , create an oauth account there and enable all the Apis of the google drive and then also go to audience and there you will see test users, place your email there. Also you have to go to you rconsent screen and create an account there and then put the redirect uri whch n8n provides you, there. If you want visual guide send me a DM and we can have a meet for more clarifications. Also mark it as a solution if you feel it.